ISTANBUL -- Riot police clashed into the early hours of today with defiant demonstrators occupying Istanbul's central Taksim Square and its adjacent park, in the country's most severe anti-government protests in decades.
The crisis has left Prime Minister Recep Tayyip Erdogan looking vulnerable for the first time in his decade in government, and has threatened to tarnish the international image of Turkey, a Muslim majority nation with a strongly secular tradition, a burgeoning economy and close ties with the United States.
Thousands of police moved into the square early Tuesday, pushing past improvised barricades set up by protesters who have swarmed through the massive square and accompanying Gezi Park in the tens of thousands for the past 12 days. Police fired repeated rounds of tear gas that rose in stinging plumes of acrid smoke from the square in running battles with protesters hurling fireworks, bottles, rocks and firebombs.
In a cat-and-mouse game that lasted all day, police repeatedly cleared the square, only for demonstrators to return. More than 30,000 converged on the square again as dusk fell and were repelled by water cannon, rubber bullets and tear gas after Istanbul's governor, Huseyin Avni Mutlu, said police came under attack by "marginal groups." The area reverberated with the echoes of exploding tear gas canisters into the night, while volunteers ferried dozens of injured people to waiting ambulances.
A peaceful demonstration against Gezi Park's redevelopment that began more than two weeks ago has grown into the biggest test of Mr. Erdogan's authority in his decade of power, sparked by outrage over a violent police crackdown May 31 against a peaceful sit-in in the park. The unrest has spread to 78 Turkish cities, with protesters championing objections to what they say is the prime minister's increasingly authoritarian style and his perceived attempts to impose a religious and conservative lifestyle on a country with secular laws -- charges he rejects.
Four people have been killed, including a policeman, and about 5,000 have been treated for injuries or the effects of tear gas, according to the Turkish Human Rights Foundation.
Gezi Park, with its thousands of camped-out young and old demonstrators, has become the protests' symbol. Both the governor and police initially pledged that only Taksim Square would be cleared, not the park. But late Tuesday night, the governor suggested a more muscular police sweep might be imminent. Tear gas was fired into the park, as protesters scrambled for cover.
"We will open the square when everything normalizes in the area, and our security forces completely control the area," Mr. Mutlu told A Haber news channel. "Our children who stay at Gezi Park are at risk, because we will clean the area of the marginal groups," he said, distinguishing troublemakers from peaceful protesters. "We won't allow our government to be seen as weak."
Some 300 miles away in Ankara, the capital, police fired water cannon and tear gas to disperse several hundred protesters -- some throwing stones -- who gathered in sympathy with the Istanbul counterparts.
Tuesday's clashes came a day after Taksim Square saw its smallest gathering since the protests began. The government had said Mr. Erdogan would meet today with some of those occupying the park to hear their views.
"The relative calm yesterday was deceptive," said Robert O'Daly, Turkey analyst for the Economist Intelligence Unit. "Mr. Erdogan's offer of dialogue appears to have been merely tactical. The appearance of riot police in the square this morning and renewed use of tear gas against the protesters fits better with his defiant rhetoric," he said.
Mr. Erdogan, a devout Muslim, says he is committed to Turkey's secular laws and denies charges of an authoritarian manner. As he defended his tough stance, he gave critics little hope of a shift in stance. "Were we supposed to kneel before them and say, 'Please remove your pieces of rags?' " he asked, referring to the dozens of banners and flags protesters had festooned in the square. "They can call me harsh, but this Tayyip Erdogan won't change."